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21.
Single particle inductively coupled plasma mass spectrometry (spICP-MS) was used to detect Ti-containing particles in heavily-used bathing areas of a river (Salt River) and five swimming pools. Ti-containing particle concentrations in swimming pools ranged from 2.8?×?103 to 4.4?×?103 particles/mL and were an order of magnitude lower than those detected in the Salt River. Measurements from the Salt River showed an 80% increase in Ti-containing particle concentration over baseline concentration during peak recreational activity (at 16:00 h) in the river. Cloud point extraction followed by transmission electron microscopy with energy dispersive X-ray analysis confirmed presence of aggregated TiO2 particles in river samples, showing morphological similarity to particles present in an over-the-counter sunscreen product. The maximum particle mass concentration detected in a sample from the Salt River (659 ng/L) is only slightly lower than the predicted no effect concentration for TiO2 to aquatic organisms (<?1 μg/L).  相似文献   
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Lung malignancies are the leading cause of cancer-related mortality. By virtue of its unique physiological function, the lung microenvironment is highly dynamic and constantly subjected to mechanical, chemical and pathogenic stimuli. Thus, the airways rely on highly organized innate defense mechanisms to rapidly protect against pathogens and maintain pulmonary homeostasis. However, in the context of lung malignancy, these defenses often provide collateral inflammatory insults that can foster tumor progression. This review summarizes the interactions between cancer cells, recruited immune cells and tissue-resident cell subpopulations, such as airway epithelial cells and alveolar macrophages, during homeostasis and disease. Furthermore, we examine the role of the lung immune landscape in response to current therapeutic interventions for cancer. Given the prevalence of lung malignancies, we propose that consideration of lung physiology as a whole is necessary to understand and treat these lethal diseases. Copyright © 2019 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.  相似文献   
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Human cadavers constitute very useful educational tools to teach anatomy in medical scholarship and related disciplines such as physiology, for example. However, as biological material, human body is subjected to decay. Thanatopraxy cares such as embalming have been developed to slow down and inhibit this decay, but the formula used for the preservation fluids are mainly formaldehyde (FA)‐based. Very recently, other formulas were developed in order to replace FA, and to avoid its toxicity leading to important environmental and professional exposure concerns. However, these alternative FA‐free fluids are still not validated or commercialized, and their efficiency is still under discussion. In this context, the use of FA‐releasing substances, already used in the cosmetics industry, may offer interesting alternatives in order to reduce professional exposures to FA. Simultaneously, the preservation of the body is still guaranteed by FA generated over time from FA‐releasers. The aim of this review is to revaluate the use of FA in thanatopraxy cares, to present its benefits and disadvantages, and finally to propose an alternative to reduce FA professional exposure during thanatopraxy cares thanks to FA‐releasers use.  相似文献   
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BK virus is the causative agent of polyomavirus-associated nephropathy, a major cause of kidney transplant failure affecting 1%-10% of recipients. Previous studies that investigated the viral source on the kidney recipient pointed that the donor is implicated in the origin of human polyomavirus BK (BKPyV) infection in recipients, but giving the low genetic variability of BKPyV this subject is still controversial. The aim of this study was to determine if BKPyV replicating in kidney recipients after transplantation is always originated from the donor. Urine and blood samples from 68 pairs of living donors and kidney recipients who underwent renal transplantation from August 2010-September 2011 were screened for BKPyV by real time polymerase chain reaction. Only three recipients presented viremia. When both donors and recipients were BKPyV positive, a larger fragment of VP1 region was obtained and sequenced to determine the level of similarity between them. A phylogenetic tree was built for the 12 pairs of sequences obtained from urine and high level of similarity among all sequences was observed, indicating that homology inferences for donor and recipient viruses must be cautiously interpreted. However, a close inspection on the donor-recipient pairs sequences revealed that 3 of 12 pairs presented considerably different viruses and 4 of 12 presented mixed infection, indicating that the source of BKPyV infection is not exclusively derived from the donor. We report that about 60% of the renal recipients shed BKPyV genetically distinct from the donor, confronting the accepted concept that the donor is the main source of recipients’ infection.  相似文献   
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